1. Field of Invention
The present invention relates to an electro-optical device, such as an active matrix liquid crystal device, an electrophoresis device, such as an electronic paper, or an electro-luminescence (EL) display device, and a method of manufacturing the same. The present invention also relates to an electronic apparatus including such an electro-optical device. Furthermore, the present invention relates to a method of manufacturing a substrate device.
2. Description of Related Art
There are related art active matrix electro-optical devices including a substrate, pixel electrodes arranged in a matrix on the substrate, thin film transistors (hereinafter, TFTs) connected to the respective pixel electrodes, and data lines and scanning lines that are connected to the respective TFTs and that are arranged to be parallel to the TFTs in column and row directions.
Such an electro-optical device includes a counter substrate that faces the substrate, a counter electrode that is provided on the counter substrate and that faces the pixel electrodes, and a liquid crystal layer interposed between the pixel electrodes and the counter electrode to thus display images. The alignment state of liquid crystal molecules in the liquid crystal layer is appropriately changed in accordance with a predetermined potential difference set between the pixel electrodes and the counter electrode. Therefore, the transmittance of light that passes through the liquid crystal layer changes to thus display images.
According to the related art electro-optical device, the TFTs, the data lines, the scanning lines, and the pixel electrodes are commonly formed on the substrate to constitute a laminated structure. To be specific, various components and interlayer insulating films are alternately arranged to form the laminated structure such that the TFTs are formed on the layer closest to the surface of the substrate. The data lines are formed on the TFTs with the interlayer insulating film interposed therebetween. The pixel electrodes are formed on the data lines with another interlayer insulating film interposed therebetween. In this case, since the TFTs, the scanning lines, and the data lines have their own heights, the heights affect their upper layers of the laminated structure to thus commonly generate a step difference on the outermost surface of the laminated structure. When the step difference is generated, for example, a rubbing process on an alignment film may be unevenly performed.
Therefore, according to the related art, a planarizing process, such as a chemical mechanical polishing (CMP) process, is performed on the outermost surface of the laminated structure. As a result, since the step difference on the outermost surface is generally made even to thus generate a flat surface, the above-mentioned problems do not occur. Also, it is possible to enhance the contrast ratio of images by performing the CMP process. An example of using the CMP process is described in Japanese Unexamined Patent Application Publication No. 2000-340567.